Multiple Network Interfaces

Some machines have more than one network interface, because they are
either routers or multihomed hosts. Each additional network interface that
is attached to the machine requires its own IPv4 address and associated name.
When you configure a router or multihomed host, you must add this information
manually to the router's /etc/inet/hosts file. See Configuring Routers for more information on configuring routers and multihomed
hosts.